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HIntersection, HIntersectionList

Syntax

HIntersection(I_1:IDEAL,...,I_n:IDEAL):IDEAL
HIntersectionList(L:LIST of IDEAL):IDEAL
    

Summary

intersection of ideals

Description

The function HIntersection returns the intersection of I_1,...,I_n using a Hilbert-driven algorithm. It differs from Intersection only when the input is inhomogeneous, in which case, HIntersection may be faster.

The function HIntersectionList applies the function HIntersection to the elements of a list, i.e., HIntersectionList([I_1,...,I_n]) is the same as HIntersection(I_1,...,I_n).

The coefficient ring must be a field.

example

    
Use R ::= Q[x,y,z];
HIntersection(Ideal(x-z,y-2z),Ideal(x-2z,y-z));
Ideal(x + y - 3z, y^2 - 3yz + 2z^2)
-------------------------------
L := [Ideal(x-z,y-2z),Ideal(x-2z,y-z)];
HIntersectionList(L);
Ideal(x + y - 3z, y^2 - 3yz + 2z^2)
-------------------------------
        
    

See Also